collectsValues ? localFutures : null;
      Runnable listener = () -> decrementCountAndMaybeComplete(localFuturesOrNull);
      for (ListenableFuture<? extends InputT> future : localFutures) {
        if (future.isDone()) {
          decrementCountAndMaybeComplete(localFuturesOrNull);
        } else {
          future.addListener(listener, directExecutor());
        }
      }
    }